The purpose of such apparatus is to verify that a watchman who is supposed to perform a round under well-defined conditions, does effectively follow the specified path for the round and does, in fact, visit various locations at specified times.
In order to monitor such a round, the apparatus may comprise a recording device carried by the watchman together with a plurality of identification keys which are permanently fixed at various locations for which verifications is to be perform. When the watchman passes each of these locations, he inserts a key carrying location-identification means into the recording device. Actuating the device by said key causes the identity of the location and the time of passage to be recorded on a recording medium, with the time of passage being provided by a clock movement within the portable device. Periodically the data recording medium may be removed from the portable device in order to verify that the watchman has performed his rounds under the conditions laid down.
There are two main types of watchman's clocks, depending on the way in which the information concerning passage via a particular location and the time of said passage is recorded. In a first type of apparatus, the data medium which may be a disk or a tape, is driven continuously by the clock movement and data representative of each location is printed on the medium. The position of said recording relative to a pre-printed time mark on the medium indicates the time at which the corresponding passage took place. It can be seen that this type of recording suffers from the drawback of requiring large-sized recording medium. Further, the recording medium is used up as a function of elapsed time rather than as a function of the number of location checks performed. In addition, time resolution is low.
In another type of apparatus, the data medium is generally in the form of a tape and is moved by one step each time an identification key is used. Under the effect of key actuation, a mechanism prints the time as given by a clock movement together with the identity of the key location. This second type of apparatus has the advantage of using up less recording medium and thus of lasting longer between refills and of providing improved resolution. However, in this type of apparatus the drive chain connecting the clock (which may be mechanical or electronic) to the data printing means and also to external time-displaying means is relatively complex and fragile. Further, the printing means in such apparatus is constituted by reels having peripheral digits enabling hours and minutes or tens of minutes to be printed. The fabrication of such print wheels is expensive since complicated molds are required in order to allow the part to be unmolded. Preferred embodiments of the present invention remedy these drawbacks by providing round monitoring apparatus of the second type, i.e. of the type in which the data medium is moved only when a recording is to be made thereon, but in which the drive chain for printing said data is simplified and the print elements are capable of being fabricated at reduced cost.
The present invention provides apparatus for monitoring the times at which a watchman passes a plurality of given locations, the apparatus comprising a plurality of keys with each key being intended to be disposeed at a respective one of said locations and being provided with a print element capable of identifying said location, the apparatus further comprising a portable recording device provided with a recording strip for simultaneously recording data representative of one of said locations together with the time of passage at said location, said portable recording device comprising a clock movement having at least an hours shaft, a disk which is fixed in rotation about said shaft and having print elements disposed around the periphery of one its faces for printing time data, means enabling one of said keys to be inserted into said portable recording device and for positioning said identification element of said key therein, strip advancing means for causing said recording strip to advance by one step, said strip advancing means causing a new portion of said strip to be placed at each step, opposite to a print element on said disk and opposite to said identification element of said key, and means for causing simultaneous printing of the time data and of the identification element on said portion of the strip.
It can thus be seen that the print mechanism and the clock movement are very simple since they are restricted to a conventional clock movement and to a disk fixed to the hours shaft of the clock movement on which the print elements for printing time information are directly fixed or made. Additionally, since the print elements are fixed around the periphery of one of the faces of the disk, the disk can be molded without any particular problems.